Process of setting tacks in porcelain teeth



I. SHFKUSAWA.

PROCESS OF SETTING TACKSJN PORCELAIN TEETH.

APPLICATION FILED wn'zn 1918.

FATE; v

IZUMI sriiKusAv/A, or orireese MACI-II, .iArAn.

PROCESS OF SETTING 'ZACKS INIORCELAIN TEETH.

Application filed JuIy QV,

to simplify the anchoring or setting of'tacks.

in an artificial tooth, so as'to permit the proper support thereof and thefirm and secure fastening of the tack in position, the

tooth being formed with a hole having a medial enlarged portion, and this hole is made by a core placed within a mold used for the formation of the artificialtooth, the core being made from inflammable substance so that when the artificial tooth is heated for the finishing of the same after the formation thereof, such heat will burn up the core, and thus free the hole therefrom-for the reception of a tack or tacks to be subsequently set or anchored therein after the removal of the formed tooth from the mold.

Another object of the invention is to firmly and securely fix a metallic tack, or the like, within an artificial tooth without requiring skilled labor and also eliminate the following out of the steps of processes heretofore known for alike purpose, which are expensive and oftentimes unsatisfactory in results. r

A further object of the invention is to provide a process, wherein headed tacks can be employed as a fastening medium for the artificial tooth, and can be readily and con veniently anchored within the body of said tooth, the cavity or hole for the tack being formed in a novel manner when the tooth is molded for subsequent reception of the headed tack, which is also fastened" within the hole or cavity in anovcl manner.

-Gther objects and advantages will be derived from the use of theprocess, which will appear from the following detailed descrip: tion, taken in connection with the accompanying drawings, illustrating the preferred embodiment of the invention, showing by way of example the molds required for practicing the invention and an artificial tooth made thereby, it being understood that changes, variations and modifications may Specification of Letters Patent. Patented Aug.

1918.1"Se1ia1 No. 247,079. 1"

be resorted to in the invention, such as come properly with-in the scope of the appended claims. I i

In the accompanying drawing:

Figure l is a plan view of one section of the mold for forming theartiiicial teeth and looking toward the inner-face thereof.

Figure 2 is a view similar to F igure' 1 of the other section of the mold looking toward its inner-face,showing indetail plural artificial teeth in theca-vities therein.

Figure 3 is a vertical transverse sectional View of the section shown in Figure 1'. Figure i is a view similar to Figure 8 taken through the section shown in Figure 2 with'the artificial toothremoved from its cavity. x Figure 5 is a vertical transversesectional view through the mold whenassembled with an artificial tooth therein and the core in place. a 3

Figure 6 is a sideelevation of=the core removed.

Figure 7 is a face view thereof. 1 Figure 8' is a side elevation of several headed tacks. v r

Figure 9 is an elevation of an artificial tooth looking toward theinner side thereof. Figure 10 is a View similar to Figure 9 showingthe tacks anchored therein.

Figure 11 is a transverse sectional view taken on the line A-B of Figure 10.

Figure 12 isa vertical sectional, view taken on the line C'D of Figure 10.

Similar reference characters indicate cor responding parts throughout the several views in the drawing. To exemplify-the carrying of the process into practice with reference to the accompanying drawing there is employed a pair of mold sections 1 and 2, respectively, each being in the form of a substantially rectangular shaped body having formed in the in-. her-face thereof a plurality of cavities or recesses .ofthe desired shape conforming to the required teeth, the sections being adapted for close contacting relation on the bringing of the sections together with their innerfaces adjoining each other. The cavities or recesses in the inner face of one section will coincide or register with the cavities or recesses corresponding. thereto in the inner-face of the adjoining section, the section 1 being formed with notches 8 in its marginal edge, while the section 2 is formed with protuberances 4 correspondingly to the sections 1 and 2the said section 1 has introduced into its cavities therein kneaded potters-clay, which is the material from which artificial teeth are made, whereupon the section 2 is placed upon the section 1 for the interlocking of these sections together to permit the formation of the artificial teeth. A I

The section 2 in each cavity therein has further formed in its body a, pocket 5, which is in the form of an elongated slot with a medial enlarged portion 6, and into, this pocket is placed a correspondingly shaped core 7, made from inflammable substance, such as a briquet, shaped as is clearly illustrated in Figures 6 and 7 of the drawing. The core 7 when held in the pocket 53in the molded section 2 will project into. the space formed by the cavities in the respective mold sections when joined together for the shaping; of the artificial teeth, so that a recess will be made in the artificial tooth, atthe inner-side thereof on the subsequent finishing of the artificial tooth in the baking thereof.

In the making of artificial teeth the mold sections 1 and 2 are initially separated from each other and a core 7 is placed within each pocket 5 in the respective cavities in the mold section 2, whereupon the cavities in the mold section 1 are filled with kneaded potters-clay, which is the material employed for making the artificial teeth, and there after said mold section 2 is superimposed. upon the mold section 1 for the oining 0% these mold: sections in the manner as shown in Figure. 5 of the drawing and pressure is. exerted upon said mold sections thus joined for compressing the material into the cavities in the respective mold sections for the proper formation of the artificial teeth thereby. The joined mold sections are per mitted to stand for the drying of the material in the cavities, and when said material is fully coagulated the mold sections are removed from the dried artificial teeth formed thereby, which have therein the core 7, and thereafter the termed teeth are baked for the finishing thereof, the baking being ei'liected by the heating oi. the teeth. During the heatingperiod each core '7 is burned up so that the finished tooth will have present therein a hole or indenture 9 correspondingly shaped to the burned core 7.

Next, there is inserted a headed tack 8 in the hole 9 formed by the burned core in the body of the tooth, the head of the tack being inserted in the enlarged central portion 10 of the hole 9 and is moved laterally toward either end of said-hole for the anchoring of the headed tack in the tooth, as the walls of the recess will engage the head of the tack and hold it fast in-such a manner that the'tack' cannotwork loose or become freed from the tooth unless excessive pressure is applied to the tack toremeve it in the direction of theenlarged portion 10 of the hole 9 for the return oi said tack to its initial or former posit-ion,y,that is, at the center of the'hole, which wouldpermit the tree removal of the tack from the tooth. It .is'pret'erable to anchor several tacks in the tooth, and iii-this event the medial-portion ot' the recess after thelanchoring' of the tacks is filled with potters-clay as at 11in Figures 1O and 11, this .m'ateriali vbeing baked thus closes the recess to prevent the removal of the tacks from the tooth and at the same time closes the hole in the inner-face of the .t00tl1i.-

It will be apparent that the tacks when anchored inqthe teeth cannot work loose or fall from the same.

From the foregoing it is, thought that the manner ot use oil? the mold and thee rrying of the process into practice will be clearly under'stooch;and, therefore, encore, extended explanation has been omitted.

l l hat is claimed is:

1.-'l.he process of making an artificial tooth provided with anchoring tacks, projecting from its rear face, which consist in. first molding; thebodyot the tooth in a double moldwith an inc-losed core of material destroyable by the heat used in baking the tooth, to. leave a transverse elongated slot in the back of the tooth having an; intermediately located enlargement, a plurality of headed tacks in the slot introduced through; the enlargement, and locating the headed ends of the tacks at o )posite ends of the slot, and thenv anchoring t 1e tacks in the tooth by material= susceptible to solidification.

. 2. The process of making artificial teeth provided with anchoring tacks n-ojcctin from its rear face, which consist in first molding; the body of the tooth in a divisible mold with an embedded coreo'l' material de stroyable by the h at used in the baking oi the tooth, to leave a transverse elongated slot in the back of the tooth with an inter mediately located enlargement, then intro ducinp; a plurality of: headed tacks in the slot through the enlargement and locatingthe headed ends of the tacks at opposite ends of the slot, and then anchoring the tacks in the teeth at opposite ends of the slot by hereto.

SHIKUSAVVA, IZUMI. [n s] 

